#!/bin/bash


# logmerge - sort and merge chronologically any kind of logfiles
#
# Copyright (c) 2012, 2014 Ildar Shaimordanov
#
# Permission is hereby granted, free of charge, to any person obtaining a 
# copy of this software and associated documentation files (the "Software"), 
# to deal in the Software without restriction, including without limitation 
# the rights to use, copy, modify, merge, publish, distribute, sublicense, 
# and/or sell copies of the Software, and to permit persons to whom the 
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included 
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 
# NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
# DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 
# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 
# USE OR OTHER DEALINGS IN THE SOFTWARE.


if [ $# -eq 0 ]
then
	cat <<EOL
Usage: $(basename $0) [options]

Small and powerful script to merge two or more logfiles so that multilined 
entries appear in the correct chronological order without breaks of entries. 
Optional arguments control an adding of descriptive fields at the beginning 
of each line in the resulting combined logfile. Reading of .gz/.bz2 files is 
available. 

-h, --hostname    Print hostname
-f, --filename    Print the name of file
-n, --linenumber  Print the numbers of lines within the original file
-d, --debug       Run in the debug mode
-t, --tempfile    Use tempfile during execution

--no-cleanup      Don't clean up the resulting file; keep interim data there
--ts-match=MATCH  The Perl regex that will look for timestamps within strings
--ts-subst=SUBST  The transformation string that will modify timestamps
EOL
	exit
fi


m_hostname=
m_filename=
m_linenumber=

m_debug=

m_tempfile=
m_tempwrite=
m_sort='|sort'

m_no_cleanup=
m_ts_match='^(\d+)/(\d+)/(\d+) (\d+):(\d+):(\d+).(\d+)'
m_ts_subst='$3$1$2$4$5$6$7'

m_files=

for m_arg in "$@"
do
	case "$m_arg" in
	-h | --hosthame)
		m_hostname='['$(hostname)']\t'
		;;
	-f | --filename)
		m_filename='[$1]\t'
		;;
	-n | --linenumber)
		m_linenumber='[$3]\t'
		;;
	-d | --debug)
		m_debug=1
		;;
	-t | --tempfile)
		m_tempfile=$(mktemp -u).$$
		m_tempwrite='>>'$m_tempfile
		m_sort='&&sort '$m_tempfile
		;;
	--no-cleanup)
		m_no_cleanup=1
		;;
	--ts-match=*)
		m_ts_match=$(echo $m_arg | cut -d= -f2-)
		;;
	--ts-subst=*)
		m_ts_subst=$(echo $m_arg | cut -d= -f2-)
		;;
	--apache-access)
		m_ts_match='\[(\d+)/(\w+)/(\d+):(\d+):(\d+):(\d+) [^\]]+\]'
		m_ts_subst='$3$m{$2}$1$4$5$6'
		;;
	--apache-error)
		m_ts_match='^\[\w+ (\w+) (\d+) (\d+):(\d+):(\d+) (\d+)\]'
		m_ts_subst='$6$m{$1}$2$3$4$5'
		;;
	*)
		m_files="$m_files \"$m_arg\""
		;;
	esac
done


logDebug() {
	[ "$m_debug" ] && echo $(date "+%F %T.%N" | cut -c-23): $1>&2
}


processFile() {
	perl -ne '
	BEGIN	{
		our $name = "'$1'";
		our $prev = "";
		our $marker = "";
		our $recnum = 0;

		our %m = (
			Jan => "01", Feb => "02", Mar => "03", Apr => "04", 
			May => "05", Jun => "06", Jul => "07", Aug => "08", 
			Sep => "09", Oct => "10", Nov => "11", Dec => "12", 
		);

		sub printIF {
			print $prev;
			$prev = "";
		}
	}

	if ( m|'"$m_ts_match"'| ) {
		printIF;

		$recnum++;
		$marker = sprintf "'"$m_ts_subst"'_%s_%07d_%%07d %%s", $name, $recnum;
	}
	$prev .= sprintf $marker, $., $_;

	END	{
		printIF;
	}
	'
}


processList() {
	logDebug "Processing the list of the files"

	eval set -- $m_files

	for m_file in "$@"
	do
		logDebug "$m_file"
		if [ ! -f "$m_file" ]
		then
			logDebug "File not found: '$m_file'"
			continue
		fi
		m_cat='<'$m_file
		echo $m_file | grep '\.gz$' >/dev/null && m_cat='gzip -dc '$m_file'|'
		echo $m_file | grep '\.bz2$' >/dev/null && m_cat='bzip2 -dc '$m_file'|'
		eval $m_cat processFile $m_file $m_tempwrite
	done
}


cleanup() {
	[ -n "$m_no_cleanup" ] && tee || perl -pe 's/^.+?_(.+?)_0*(\d+)_0*(\d+) /'"$m_hostname""$m_filename""$m_linenumber"'/'
}


if [ "$m_tempfile" ]
then
	logDebug "Creating $m_tempfile"
	cp /dev/null $m_tempfile
fi

eval processList $m_sort | cleanup

if [ "$m_tempfile" ]
then
	logDebug "Deleting $m_tempfile"
	rm $m_tempfile
fi


#EOF


